Method of Forming a Mycological Product

ABSTRACT

The method grows a mycelial mass over a three-dimensional lattice such that a dense network of oriented hyphae is formed on the lattice. Growth along the lattice results in mycelium composite with highly organized hyphae strands and allows the design and production of composites with greater strength in chosen directions due to the organized nature of the supporting mycelia structure.

This is a Division of U.S. Ser. No. 13/856,086, filed Apr. 3, 2013 whichis a Division of U.S. Ser. No. 12/001,556, filed Dec. 12, 2007, now U.S.Pat. No. 9,485,917.

This invention claims the benefit of Provisional Patent Application No.60/875,243 filed Dec. 15, 2006 and Provisional Patent Application No.60/927,458 filed May 3, 2007, the contents of each being incorporated byreference herein.

This invention relates to a method of forming a mycological product.

BACKGROUND OF THE INVENTION

Materials are produced today using a range of processes ranging fromtime intensive outdoor growth and harvesting to energy intensive factorycentric production. As demand for raw goods and materials rise, theassociated cost of such materials rises. This places greater pressure onlimited raw materials, such as minerals, ores, and fossil fuels, as wellas on typical grown materials, such as trees, plants, and animals.Additionally, the production of many materials and composites producessignificant environmental downsides in the form of pollution, energyconsumption, and a long post use lifespan.

Conventional materials such as expanded petroleum based foams are notbiodegradable and require significant energy inputs to produce in theform of manufacturing equipment, heat and raw energy.

Conventionally grown materials, such as trees, crops, and fibrousplants, require sunlight, fertilizers and large tracts of farmable land.

Finally, all of these production processes have associated wastestreams, whether they are agriculturally or synthetically based.

Fungi are some of the fastest growing organisms known. They exhibitexcellent bioefficiency, of up to 80%, and are adept at converting rawinputs into a range of components and compositions. Fungi are composedprimarily of a cell wall that is constantly being extended at the tipsof the hyphae. Unlike the cell wall of a plant, which is composedprimarily of cellulose, or the structural component of an animal cell,which relies on collagen, the structural oligosaccharides of the cellwall of fungi relay primarily on chitin. Chitin is strong, hardsubstance, also found in the exoskeletons of arthropods. Chitin isalready used within multiple industries as a purified substance. Theseuses include: water purification, food additives for stabilization,binders in fabrics and adhesives, surgical thread, and medicinalapplications.

Given the rapid growth times of fungi, its hard and strong cellularwall, its high level of bioeffeciency, its ability to utilize multiplenutrient and resource sources, and, in the filamentous types, its rapidextension and exploration of a substrate, materials and composites,produced through the growth of fungi, can be made more efficiently, costeffectively, and faster, than through other growth processes and canalso be made more efficiently and cost effectively then many syntheticprocesses.

Numerous patents and scientific procedure exists for the culturing offungi for food production, and a few patents detail production methodsfor fungi with the intent of using its cellular structure for somethingother than food production. For instance U.S. Pat. No. 5,854,056discloses a process for the production of “fungal pulp”, a raw materialthat can be used in the production of paper products and textiles.

Accordingly, it is an object of the invention to provide method ofproducing a mycological product in an economical manner.

Briefly, the invention provides a method that uses the growth of hyphae,collectively referred to as mycelia or mycelium, to create materialscomposed of the fungi cellular tissue.

The method employs a step for growing filamentous fungi from any of thedivisions of phylum Fungi. The examples that are disclosed focus oncomposites created from basidiomycetes, e. g., the “mushroom fungi” andmost ecto-mycorrhizal fungi. But the same processes will work with anyfungi that utilizes filamentous body structure. For example, both thelower fungi, saphrophytic oomycetes, the higher fungi, divided intozygomycetes and endo-mycorrhizal fungi as well as the ascomycetes anddeutoeromycetes are all examples of fungi that possess a filamentousstage in their life-cycle. This filamentous stage is what allows thefungi to extend through its environment creating cellular tissue thatcan be used to add structural strength to a loose conglomeration ofparticles, fibers, or elements.

These and other objects and advantages will become more apparent fromthe following detailed description taken in conjunction with theaccompanying drawings wherein:

FIG. 1 illustrates a simplified flow chart of a method employed formaking a fungi bonded material in accordance with the invention;

FIG. 2 illustrates a schematic life cycle of Pleurotus ostreatus;

FIG. 3 illustrates an inoculated substrate before growth in an enclosurein accordance with the invention;

FIG. 4 illustrates an inoculated substrate after three days of growth inaccordance with the invention;

FIG. 5 illustrates an inoculated substrate nearing the end of the growthin accordance with the invention;

FIG. 6 illustrates a final composite of one embodiment composed ofnutrient particles and a bulking particle in accordance with theinvention; and

FIG. 7 illustrates a plastic lattice supporting mycelium growth inaccordance with the invention.

Referring to FIG. 1 , the method of making a self-supporting structuralmaterial is comprised of the following steps.

-   -   0. Obtain substrate constituents, i.e. inoculum in either a        sexual or asexual state, a bulking particle or a variety of        bulking particles, a nutrient source or a variety of nutrient        sources, a fibrous material or a variety of fibrous materials        and water.    -   1. combining the substrate constituents into a growth media or        slurry by mixing the substrate materials together in volumetric        ratios to obtain a solid media while the inoculum is applied        during or following the mixing process.    -   2. applying the growth media to an enclosure or series of        enclosures representing the final or close to final geometry.        The media is placed in an enclosure with a volume that denotes        the composite's final form including internal and external        features. The enclosure may contain other geometries embedded in        the slurry to obtain a desired form.    -   3. growing the mycelia, i.e. filamentous hyphae, through the        substrate. The enclosure is placed in an environmentally        controlled incubation chamber as mycelia grows bonding the        bulking particles and consuming the allotted nutrient(s).    -   3a. repeating steps 1-3 for applications in which materials are        layered or embedded until the final composite media is produced.    -   4. removing the composite and rendering the composite        biologically inert. The living composite, i.e. the particles        bonded by the mycelia, is extracted from the enclosure and the        organism is killed and the composite dehydrated.    -   5. completing the composite. The composite is post-processed to        obtain the desired geometry and surface finish and laminated or        coated.

The inoculum is produced using any one of the many methods known for thecultivation and production of fungi including, but not limited to,liquid suspended fragmented mycelia, liquid suspended spores and myceliagrowing on solid or liquid nutrient.

Inoculum is combined with the engineered substrate, which may becomprised of nutritional and non-nutritional particles, fibers, or otherelements. This mixture of inoculum and substrate is then placed in anenclosure.

In step 3, hyphae are grown through the substrate, with the net shape ofthe substrate bounded by the physical dimensions of the enclosure. Thisenclosure can take on any range of shapes including rectangles, boxes,spheres, and any other combinations of surfaces that produce a volume.Growth can occur both inside the enclosure and outside of the enclosuredepending on desired end shape. Similarly, multiple enclosures can becombined and nested to produce voids in the final substrate. Otherelements embedded with the slurry may also become integrated into thefinal composite through the growth of the hyphae.

The hyphae digest the nutrients and form a network of interconnectedmycelia cells growing through and around the nutrients and through andaround the non-nutrient particles, fibers, or elements. This growthprovides structure to the once loose particles, fibers, elements, andnutrients, effectively bonding them in place while bonding the hyphae toeach other as well.

In step 4, the substrate, now held tightly together by the mycelianetwork, is separated from the enclosure, and any internal enclosures orelements are separated away, as desired.

The above method may be performed with a filamentous fungus selectedfrom the group consisting of ascomycetes, basidiomycetes,deuteromycetes, oomycetes, and zygomycetes. The method is preferablyperformed with fungi selected from the class: Holobasidiomycete.

The method is more preferably performed with a fungus selected from thegroup consisting of:

-   -   pleurotus ostreatus    -   Agrocybe brasiliensis    -   Flammulina velutipes    -   Hypholoma capnoides    -   Hypholoma sublaterium    -   Morchella angusticeps    -   Macrolepiota procera    -   Coprinus comatus    -   Agaricus arvensis    -   Ganoderma tsugae    -   Inonotus obliquus

The method allows for the production of materials that may, in variousembodiments, be characterized as structural, acoustical, insulating,shock absorbing, fire protecting, biodegrading, flexible, rigid, waterabsorbing, and water resisting and which may have other properties invarying degrees based on the selection of fungi and the nutrients. Byvarying the nutrient size, shape, and type, the bonded bulking particle,object, or fiber, size, shape, and type, the environmental conditions,and the fungi strain, a diverse range of material types, characteristicsand appearances can be produced using the method described above.

The present invention uses the vegetative growth cycle of filamentousfungi for the production of materials comprised entirely, or partiallyof the cellular body of said fungi collectively known as mycelia.

FIG. 2 shows a schematic representation of the life cycle of PleareotusOstreatus, filamentous fungi. The area of interest for this invention isthe vegetative state of a fungi's life cycle where a fungi is activelygrowing through the extension of its tube like hyphae.

In this Description, the following definitions are specifically used:

Spore: The haploid, asexual bud or sexual reproducing unit, or “seed”,of a fungus.

Hyphae: The thread-like, cellular tube of filamentous fungi which emergeand grow from the germination of a fungal spore.

Mycelium: The collection of hyphae tubes originating from a single sporeand branching out into the environment.

Inoculum: Any carrier, solid, aerated, or liquid, of a organism, whichcan be used to transfer said organism to another media, medium, orsubstrate.

Nutrient: Any complex carbohydrate, polysaccharide chain, or fattygroup, that a filamentous fungi can utilize as an energy source forgrowth.

Fruiting Body: A multicellular structure comprised of fungi hyphae thatis formed for the purpose of spore production, generally referred to asa mushroom.

Fungi Culturing for Material Production Methodology

Procedures for culturing filamentous fungi for material production.

All methods disclosed for the production of grown materials require aninoculation stage wherein an inoculum is used to transport a organisminto a engineered substrate. The inoculum, carrying a desired fungistrain, is produced in sufficient quantities to inoculate the volume ofthe engineered substrates; inoculation volume may range from as low as1% of the substrates total volume to as high as 80% of the substratesvolume. Inoculum may take the form of a liquid carrier, solid carrier,or any other known method for transporting a organism from one growthsupporting environment to another.

Generally, the inoculum is comprised of water, carbohydrates, sugars,vitamins, other nutrients and the fungi. Depending on temperature,initial tissue amounts, humidity, inoculum constituent concentrations,and growth periods, culturing methodology could vary widely.

Grown Material within an Enclosure

FIG. 3 shows a side view of one embodiment i.e. an insulating composite,just after inoculation has taken place.

In this embodiment, a group of nutritional particles 1 and a group ofinsulating particles 2 were placed in an enclosure 5 to form anengineered substrate 6 therein. The enclosure 5 has an open top anddetermines the final net shape of the grown composite. Thereafter, aninoculum 3 was applied directly to the surface of the engineeredsubstrate 6.

Shortly after the inoculum 3 was applied to the surface, hyphae 4 werevisible extending away from the inoculum 3 and into and around thenutritional particles 1 and insulating particles 2.

FIG. 4 shows a side view of the same embodiment described above, i.e. aninsulating composite, approximately 3 days after the inoculum 3 wasapplied to the surface of the engineered substrate 6. Hyphae 3 have nowpenetrated into the engineered substrate 6 and are beginning to bondinsulating particles 2 and nutritional particles 1 into a coherentwhole.

FIG. 5 . shows a side view of the same embodiment of FIGS. 3 and 4 ,i.e. an insulating composite, approximately 7 days after the inoculum 3was applied to the surface of the engineered substrate 6. Hyphae 3,collectively referred to as mycelia 7, have now fully colonized the tophalf of engineered substrate 6, bonding insulating particles 2 andnutritional particles 1 into a coherent whole.

FIG. 6 shows a side view of the same embodiments of FIGS. 3, 4 and 5 ,i.e. an insulating composite, after the engineered substrate 6 has beenfully colonized and bonded by mycelia 7. A cutaway view shows a detailof a single insulating particle bound by a number of hyphae 4. Alsoshown within this embodiment are fibers 9 bound within mycelia 8.

Static Embodiment—Composite

FIG. 6 shows a perspective view of one embodiment of a mycelia bondedcomposite composed of nutritional particles, bulking particles, fibers,and insulating particles. In this embodiment of a mycelia bondedcomposite, the following growth conditions and materials were used: Theengineered substrate was composed of the following constituents in thefollowing percentages by dry volume:

-   -   1. Rice Hulls, purchased from Rice World in Arkansas, 50% of the        substrate.    -   2. Horticultural Perlite, purchased from World Mineral of Santa        Barbra, California, 15% of the substrate.    -   3. DGS, dried distillers grains, sourced from Troy Grain Traders        of Troy NY, 10% of the substrate.    -   4. Ground cellulose, composed of recycled paper ground into an        average sheet size of 1 mm×1 mm, 10% of the substrate.    -   5. Coco coir, sourced from Mycosupply, 10% of the substrate.    -   6. Inoculum composed of rye grain and inoculated with Plearotus        Ostreatus, 3% of the substrate.    -   7. Birch sawdust, fine ground, 2% of the substrate by volume.    -   8. Tap water, from the Troy Municipal Water supply, was added        until the mixture reached field capacity, an additional 30% of        the total dry substrate volume was added in the form of water.

These materials were combined together in a dry mix process using arotary mixer to fully incorporate the particles, nutrients, and fibers.Water was added in the final mixing stage. Total mixing time was 5minutes.

The enclosures were incubated for 14 days at 100% RH humidity and at atemperature of 75° Fahrenheit. The enclosures serve as individualmicroclimates for each growing substrate set. By controlling the rate ofgas exchange, humidity can be varied between RH 100%, inside anenclosure, and the exterior humidity, typically RH 30-50%. Eachrectangular enclosure fully contained the substrate and inoculumpreventing gaseous exchange. Opening the enclosures lids after 5 and 10days allowed gaseous exchange. In some cases, lids included filter disksallowing continuous gas exchange.

After 14 days of growth, the enclosures were removed from the incubator.The loose fill particles and fibers having been bonded into a cohesivewhole by the fungi's mycelium produced a rectangular panel withdimensions closely matching those of the growth enclosure. This panelwas then removed from the enclosure by removing the lid, inverting thegrowth enclosure, and pressing gently on the bottom.

The mycelia bonded panel was then transferred to a drying rack within aconvection oven. Air was circulated around the panel until fully dry,about 4 hours. Air temperature was held at 130 degrees Fahrenheit.

After drying, the now completed composite is suitable for directapplication within a wall, or can be post processed to include otherfeatures or additions including water resistant skins, stiff exteriorpanel faces, and paper facings.

Within the above embodiment, the ratios and percentages of bulkingparticles, insulating particles, fibers, nutrients, inoculum, and watercan be varied to produce composites with a range of properties. Thematerials expanded perlite compositions can vary from 5%-95% of thecomposite by volume. Other particles, including exfoliated vermiculite,diatomic earth, and ground plastics, can be combined with the perlite orsubstituted entirely. Particle sizes, from horticultural grade perliteto filter grade perlite are all suitable for composite composition andmany different composite types can be created by varying the ratio ofperlite particle size or vermiculite or diatomic earth particle size.

Rice hulls can compose anywhere from 5-95% of the composite material byvolume. Fibers can compose from 1-90% of the material by volume. DGS cancompose between 2-30% of the substrate by volume. The inoculum, when inthe form of grain, can compose between 1-70% of the substrate by volume.The inoculum, when in other forms can comprise up to 100% of thesubstrate. Ground cellulose, sourced from waste paper, can compose from1-30% of the substrate by volume.

Other embodiments may use an entirely different set of particles fromeither agricultural or industrial sources in ratios sufficient tosupport the growing of filamentous fungi through their mass.

Though not detailed in this embodiment, the engineered substrate canalso contain elements and features including: rods, cubes, panels,lattices, and other elements with a minimum dimension 2 times largerthan the mean diameter of the largest average particle size.

In this embodiment, the fungi strain Pleurotus ostreatus was grownthrough the substrate to produce a bonded composite. Many otherfilamentous fungi's could be used to produce a similar bonding resultwith differing final composite strength, flexibility, and water sorptioncharacteristics.

In this embodiment, the substrate was inoculated using Pleurotusostreatus growing on rye grain. Other methods of inoculation, includingliquid spore inoculation, and liquid tissue inoculation, could be usedwith a similar result.

Incubation of the composite was performed at 100% RH humidity at 75°Fahrenheit. Successful incubation can be performed at temperatures aslow as 35° Fahrenheit and as high as 130° Fahrenheit. RH humidity canalso be varied to as low as 40%.

Drying was accomplished using a convection oven but other methods,including microwaving and exposing the composite to a stream of cool,dry air, are both viable approaches to moisture removal.

Structure or lattice for mycelium growth—FIG. 7

Mycelia based composites may be grown without the explicit use of aloose fill particle substrate. In fact, by creating a highly organizedgrowth substrate, formations of mycelia composites can be created thatmight not normally arise when growth is allowed to propagate naturallythrough loose particles.

One way of adding an engineered structure to mycelium composites is toproduce a digestible or non-digestible 3-d framework within which themycelium grows. This framework may be formed from the group including:starch, plastic, wood, or fibers. This framework may be orientedorthogonally or oriented in other ways to produce mycelia growthprimarily along the axis's of the grid. Additionally, this grid may beflexible or rigid. Spacing between grid members can range from 0.1 mm toupwards of 10 cm.

Growth along these engineered grids or lattices results in myceliumcomposites with highly organized hyphae strands allowing the design andproduction of composites with greater strength in chosen directions dueto the organized nature of the supporting mycelia structure.

Such an arrangement also allows the development of organized myceliumstructures composed primarily of hyphae rather than of bulking andnutritional particles.

To produce one embodiment of such a structure the following steps aretaken:

Referring to FIG. 7 , a three-dimensional lattice, formed of sets of 1mm×1 mm plastic grids 14 oriented orthogonally, is coated in a mixtureof starch and water. This mixture is composed of 50% starch, and 50% tapwater by volume. These materials were sourced as organic brown riceflour, and tap water, from the Troy NY municipal water supply,respectively.

This lattice is placed on/in a bed of inoculum containing Plearotusostreatus on a suitable nutrient carrier. The lattice and inoculum bedare then placed in an environment held at the correct temperature,between 55-95 degrees Fahrenheit, and humidity, between 75% RH and 100%RH, to stimulate mycelia growth.

FIG. 7 shows a cutaway of a grid based mycelium composite. Only twointersecting grids are shown, but the composite would actually becomposed of a series of grids extending axially spaced 1 mm apart. Gridsquares have an edge length of 1 mm. Here, mycelium 8 is shown growingthrough the grids 14. This thickly formed mycelia mat forms the bulk ofthe volume of the composite.

The mycelium is grown over and through the grid producing a densenetwork of oriented hyphae. Overtime, the hyphae will interweaveproducing a dense 3-D mat. After 1 to 2 weeks of growth, the grid isremoved from the incubator and dried, using either a convection oven, orother means to remove the water from the mycelium mass. Once dried themycelia composite can be directly used, or post processed for otherapplications.

Within this embodiment, the grid may or not provide the mycelia anutrient source, but if nutrients are not provided within the gridframework, the grid must be placed in close proximity to an inoculumcontaining a nutrient source as to allow the fungi to transportnutrients into the grid based mycelium for further cellular expansion.

The invention thus provides a new method of producing grown materials.These materials may be flexible, rigid, structural, biodegradable,insulating, shock absorbent, hydrophobic, hydrophilic, non-flammable, anair barrier, breathable, acoustically absorbent and the like. All of theembodiments of this invention can have their material characteristicsmodified by varying the organism strain, nutrient source, and otherparticles, fibers, elements, or other items, included in the growthprocess.

Further, the invention provides a method of making a mycologicalmaterial that can be used for various purposes, such as, for foodproduction.

What is claimed is:
 1. A method of making a mycological productcomprising the steps of providing a three-dimensional framework; andgrowing mycelium on said framework in an environment held at atemperature and humidity to stimulate mycelia growth for a timesufficient for the mycelia growth to form a dense network of orientedhyphae on said framework.
 2. A method as set forth in claim 1 whereinsaid framework is digestible.
 3. A method as set forth in claim 1 whichfurther comprises the step of coating said framework with a mixture ofstarch and water prior to said step of growing mycelium on saidframework.
 4. A method as set forth in claim 3 which further comprisesthe step of placing the coated framework on a bed of inoculum containingPlearotus ostreatus on a nutrient carrier prior to said step of growingmycelium on said framework.
 5. A method of forming a product comprisingproviding a three-dimensional lattice having at least two grids orientedorthogonally to each other; coating the lattice with a mixture of starchand water; thereafter placing the lattice in a bed of inoculumcontaining Plearotus ostreatus in a nutrient carrier; thereafterstimulating mycelium growth over and through said grids of the latticeto produce a dense network of hyphae; and allowing said hyphae tointerweave over time to produce a mat of said thickly formed mycelia onsaid lattice.
 6. A method as set forth in claim 5 further comprising thestep of drying said mat.